Deploy KEDA HTTP add-on components independently

[Tensho]

To support interceptor deployment per target namespace, let the user deploy the chart on a per-component basis. Right now it's all-in-one – chart deploys all 3 components (controller, scaler, interceptor).

Use-Case

I have a GKE cluster with many target namespaces, e.g. xyz, and one keda namespace. The keda namespace contains the cluster-wide KEDA core. A target namespace contains GKE ingress (GLB) → k8s service → k8s deployment (pods). I'm supposed to run a centralised/shared KEDA HTTP add-on interceptor in keda namespace, but ExternalName service is required in the target namespace to proxy ingress in target namespace to the interceptor service in keda namespace. However, GKE Ingress (Gateway API as well) doesn't allow setting an external service as a backend.

On the other hand, the current chart doesn't allow splitting components (controller, scaler, interceptor) deployment across the namespaces. Hence, I can't deploy interceptor per target namespace and controller + scaler in keda namespace.

Specification

• Provide chart toggles to deploy components independently, supporting components split across namespaces.

Notes

Don't hesitate to point me in the right direction if I'm looking into this from the wrong side.